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991.
992.
993.
Pasquale Calapso 《Annali di Matematica Pura ed Applicata》1929,7(1):213-224
Sunto. In questa Memoria è stabilita una trasformazione di una data congruenza ciclica(G) in una nuova congruenza ciclica (G
1), attraverso un sistema di cinque sfere a due a due ortogonali. L'equazione diLaplace per i parametri direttori della rettaG
1 èl'aggiunta di quella relativa a(G). La (G
1) è generale se tale è la(G). 相似文献
994.
Pasquale Calapso 《Annali di Matematica Pura ed Applicata》1929,7(1):225-229
Sunto. In questa Memoria vengono formati gl'inviluppi di sfere, sulle cui focali si corrispondono le linee di curvatura e le linee
asintotiche, con la considerazione della congruenzaaggiunta; il problema è ridotto ad un sistema diCauchy e la soluzione generale dipende da quattro funzioni arbitrarie di una sola variabile. 相似文献
995.
Salvatore Pincherle 《Annali di Matematica Pura ed Applicata》1936,15(1):243-308
Alcuni dei risultati qui contenuti trovansi riassunti nella Nota postuma:S. Pincherle,Sulla permutabilità negli operatori lineari, ? Bollettino dell'Un. Mat. It. ?, t. 15 (1936), pp. 153–161; va inoltre avvertito che — colla scomparsa del compianto Maestro
— l'ultimo capitolo della presente Memoria è rimasto incompleto, ciò che però non nuoce all'organicità del lavoro. 相似文献
996.
997.
Nikhil M. Kriplani David P. Nackashi Christian J. Amsinck Neil H. Di Spigna Michael B. Steer Paul D. Franzon Ramon L. Rick Gemma C. Solomon Jeffrey R. Reimers 《Chemical physics》2006
Two efficient, physically based models for the real-time simulation of molecular device characteristics of single molecules are developed. These models assume that through-molecule tunnelling creates a steady-state Lorentzian distribution of excess electron density on the molecule and provides for smooth transitions for the electronic degrees of freedom between the tunnelling, molecular-excitation, and charge-hopping transport regimes. They are implemented in the fREEDA™ transient circuit simulator to allow for the full integration of nanoscopic molecular devices in standard packages that simulate entire devices including CMOS circuitry. Methods are presented to estimate the parameters used in the models via either direct experimental measurement or density-functional calculations. The models require 6–8 orders of magnitude less computer time than do full a priori simulations of the properties of molecular components. Consequently, molecular components can be efficiently implemented in circuit simulators. The molecular-component models are tested by comparison with experimental results reported for 1,4-benzenedithiol. 相似文献
998.
Nonisothermal kinetics of the solid‐solid phase transition in (n‐C10H21NH3)2ZnCl4(C10Zn), (n‐C16H33NH3)2ZnCl4(C16Zn) and their binary system were determined by Kissinger and Ozawa methods from DSC measurements. The activation energy Ea of the binary system shows a waving dependence on WC10Zn%, which is caused by not only an intermediate (C10H21NH3)(n‐C16H33NH3)ZnCl4 but also three solid solution ranges (α, β, γ) in the phase diagram of C10Zn‐C16Zn. The variations of the layer d‐spacing are also convenient for the above result. 相似文献
999.
Funk T Kennepohl P Di Bilio AJ Wehbi WA Young AT Friedrich S Arenholz E Gray HB Cramer SP 《Journal of the American Chemical Society》2004,126(18):5859-5866
We show that X-ray magnetic circular dichroism (XMCD) can be employed to probe the oxidation states and other electronic structural features of nickel active sites in proteins. As a calibration standard, we have measured XMCD and X-ray absorption (XAS) spectra for the nickel(II) derivative of Pseudomonas aeruginosa azurin (NiAz). Our analysis of these spectra confirms that the electronic ground state of NiAz is high-spin (S = 1); we also find that the L(3)-centroid energy is 853.1(1) eV, the branching ratio is 0.722(4), and the magnetic moment is 1.9(4) mu(B). Density functional theory (DFT) calculations on model NiAz structures establish that orbitals 3d(x2-y2) and 3d(z2) are the two valence holes in the high-spin Ni(II) ground state, and in accord with the experimentally determined orbital magnetic moment, the DFT results also demonstrate that both holes are highly delocalized, with 3d(x2-y2) having much greater ligand character. 相似文献
1000.